A sentence expresses a complete thought. Knowing when a thought is complete is important in machines with natural language, turn-taking, speech-based, human-machine interfaces. It tells the system when to speak in a conversation, effectively cutting off the user.
Some systems with speech interfaces that attempt to detect the end of a sentence (EOS) based on an amount of time with no voice activity detection (NVAD) use too short of a timeout period and, as a result, cut off people who speak slowly or with long pauses between words or clauses of a sentence.
Some systems that attempt to detect an EOS based on an amount of time with NVAD use a long timeout period and, as a result, are slow to respond at the end of sentences.
Both problems frustrate users.